21054235413 has 4 divisors (see below), whose sum is σ = 28072313888. Its totient is φ = 14036156940.

The previous prime is 21054235403. The next prime is 21054235439. The reversal of 21054235413 is 31453245012.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 21054235413 - 2¹⁰ = 21054234389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21054235403) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3509039233 + ... + 3509039238.

It is an arithmetic number, because the mean of its divisors is an integer number (7018078472).

Almost surely, 2^21054235413 is an apocalyptic number.

It is an amenable number.

21054235413 is a deficient number, since it is larger than the sum of its proper divisors (7018078475).

21054235413 is an equidigital number, since it uses as much as digits as its factorization.

21054235413 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7018078474.

The product of its (nonzero) digits is 14400, while the sum is 30.

The spelling of 21054235413 in words is "twenty-one billion, fifty-four million, two hundred thirty-five thousand, four hundred thirteen".